Since the terrorist events of Sep. 11, 2001, the likelihood of future terrorist attacks is acknowledged to be higher than in the past. As a result, the public has greater expectations for security, prevention, interdiction and incident site management. Radiological and other agents have a particularly high potential for psycho-social impacts on political and economic systems. The malicious dispersal or the clandestine placement of radiological materials or other agents could be used to attack private, public and economic targets.
Radiological, nuclear, biological or chemical agents could be acquired by terrorists through clandestine theft or low level military operations and moved, possibly undetected, to urban population areas or to targets of high symbolic value.
The applicants have accordingly recognized a need for improved systems and methods of detecting and tracking nuclear, radiological, biological or chemical threats.